Automatic recycling time switch



. Jan? 30, 1968 R. D. RULSEH 3,366,801

AUTOMATICRECYCLING TIME SWITCH Filed Feb. 19, 1965 6 Sheets-Sheet 1 I NVENTOR Foes/e0, PUL 55H ATTORNEY Jan- 30, 1968 R. D. RULSEH 3,366,801

AUTOMATIC RECYCLING TIME SWITCH Filed Feb. 19, 1965 6 Sheets-$heet 2 36 INVENTOR ROERQPl/LSEH ATTORNEY Jan. 30, 1968 R. o. RULSEH 3,366,301

I AUTOMATIC RECYCLING TIME SWITCH Filed Feb. 19, 1965 6 Sheets-Sheet 5 I N VENTOR.

R0 520, RULSEH. Y

Jan. 30, 1968 R. D. RULSEH 3,366,801

AUTOMATIC RECYCLING TIME SWITCH Filed Feb. 19, 1965 6 Sheets-Sheet 4 I N VENTOR. ROEEQ RULSEH Jan. 30, 1968 R D. RULSEH 3,366,801

AUTOMATIC RECYCLING TIME SW-ITCH Filed Feb. 19, v1965 6 SheetsSheet 5 I NVENTOR Roaeepfiuzs EH ATTORNEY Jan. 30, 1968 R, D. RULSEH 3,366,801

AUTOMATIC RECYCLING TIME SWITCH Filed Feb. 19, 1965 6 Sheets-Sheet. 6

6 W/ TCI/ CONTROL CONTROL INAC TlV/J TED COND/T/ONED M.w Moro/z M0 TOR ON I I OFF LIGHTS LIGHTS 0 OFF I I 7:00 PM MIDNIGHT lvaorv 6:00PM 7 00PM I T I pllomcaNoucTok TIME/E: TIMER: CYCLE (a) TUK/v5 LAW/f5 ON (a) TURNS LIGHTS OFF (4) rug v5 PE 7'5 (6) TUK/VS MOTOK ON I M070? OFF (0) lNflCT/VA 755 (b) COND/T/0N5 SWITCH CONTROL SWITCH CONTROL T/MEE I hi6 f 09 U4 w Ki /6\ M "/50 I r 51. 1 1 /1! K15 W J J I /37 INVENTOR fioaelepfiz/Lsew ATTOR NE Y atet 3,3653% Patented Jan. 39, 1968 3,366,801 AUTOMATIC RECYCLING TIME SWITCH Roger David Rulseh, Two Rivers, Wis., assignor to American Machine & Foundry Company, a corporation of New Jersey Filed Feb. 19, 1965, Ser. No. 433;M6

18 Claims. (Cl. 307-117) ABSTRACT OF THE DHSCLOSURE A timer which automatically resets after a power failure having a motor and a dial driven by the motor to make a complete revolution in less than twenty-four hours whereupon the motor is turned off, the timer is conditioned for subsequent operation, and the remaining time until subsequent operation is a pause period provided for resetting. A photoelectric circuit is provided to turn the motor on, and to operate a load switch to a first state which after a predetermined time period is returned to its original state by means operatively associated with the driven dial.

This invention relates generally to an electrically driven timer for controlling the operation of an electrical device, and particularly to such a timer which automatically retimes itself in response to a daily occurring natural condition.

More particularly, this invention relates to an electrically driven timer combined with a device responsive to a predetermined value of natural light intensity for automatically operating a switch and for retiming the timer during a reasonable time interval following the resumption of power after a power failure.

Although the timer of this invention has many uses, it

is particularly adapted to control outdoor lighting such as used on billboards or other illuminated advertising media where the lighting is turned on at dusk and is turned off several hours later, when the number of expected observers of the advertising are then so few that further illumination is not warranted.

The timer of this invention can also be used for the control of street lighting and other illumination which normally is turned on at dusk and turned off a certain numberof hours later as at dawn of the following day.

With the known forms of electric motor driven timers there is a significant shortcoming, namely that these timers must be retimed whenever there is a power failure. In the case where the timer is comprised of an electrically driven time switch alone, the lights are turned on at'a certain hour each evening and are turned off at a certain hour the following morning. In the event of a power failure of for example two hours, the lights turn on two hours late in the evening and turn off two hours late the following morning. Hence, it is necessary for maintenance people to readjust all timers in the area affected by the power failure to maintain a predetermined cycle of operation. Another disadvantage of a timer alone is its inability to compensate for seasonal variations in the time of sunset and dusk. Hence, unless the timer is adjusted several times a year, the lights will not turn on until after dark during the winter months or will turn on before dark during the summer months, (Assuming that the timer is located north or south of the equator.)

Also known are lighting control devices which include only a light responsive switch which turns the lights on at dusk and turns the lights off at dawn. Such devices, of course, do not require retiming after a power failure because there is no timer. Under normal circumstances such devices are satisfactory but have limited application since the lights can be turned off only at dawn. Also it has been found that unless the light responsive switches for such systems are very carefully placed and shielded from extraneous intermittent illumination such as automobile head lights or lightening, for example, the lights may be turned off and on several times during the hours of darkness. Such intermittent operation obviously decreases the operating life of both the lights and the switches which control the lights. Darkness during the daylight hours as caused by storm clouds also frequently operates the lights with corresponding detrimental effects. Hence, even though a control system operated solely by a light responsive switch need not be retimed after a power failure, other deficiencies are encountered which detract from the desirability of such a system.

A prior system which has proven somewhat satisfactory is one in which a photocell turns lights on at dusk and a timer which runs 24 hours each day turns the lights off at a predetermined time. Such an arrangement adds flexibility to the system since the timer can be preset to turn off the lights at any time of day or night. To compensate for power failures the timer includes an electrically Wound spring operated clock mechanism, the spring wound clock mechanism being effective to continue to drive the timer for several hours or even days during which there is no power because of a power failure. Such an arrangement of course does away with the necessity of retiming the timer after each power failure. The disadvantage of such systems is the prohibitive cost of the electrically wound spring operated clock.

Other attempts to avoid the problems encountered by power failures includes separate sources of power such as batteries which power the timer motor, for at least several hours in the event of power failure.

In another prior system a photocell is combined with a timer to turn lights on at dusk and off at dawn. The timer controls the photocell in such a manner that the photocell can turn the lights on only after a predetermined time in the afternoon, and can turn the lights off only after a predetermined time in the morning. A spring motor, wound intermittently from an electric power source, runs continuously to drive the timer and also to prevent an improper cycle of operation after a power failure. The basic purpose of this prior system is to automatically compensate for seasonal variations in the hour of dusk when the lights are turned on. Such compensation is effected by a cam which is declutched from a shaft driven by the spring motor, during the interval when the photocell can operate the lights. As soon as the photocell operates the cam is again clutched to the shaft. The operation is such that the photocell is conditioned and the cam stopped about 6 hours prior to the expected operation of the photocell. This system has the disadvantages of turning the lights off only at dawn, and of requiring a special electrically wound spring motor to maintain a proper cycle of operation in the event of power failure.

The present invention alleviates all the problems encountered in the past by providing a timer having a conventional electric timer motor which drives a dial to make one complete revolution in a time period of less than 24 'hours, preferably 20 hours, and then the motor is turned off. The timer is so constructed that a light responsive switch can operate a switch of the timer only when the timer motor is off and the timer is conditioned for operation. 7

Operation of the light responsive switch switches the controlled load (for example, street lights) on and also re-energizes the timer motor so that the timer again runs for 20 hours. The driven dial of the timer then turns the lights off a predetermined time after they are turned on by the light responsive switch. Since operation of the light responsive switch is also effective to deactivate the circuit controlled by the light responsive switch, the lights are operated on only once each day and hence, problems encountered by on and off operation of the lights due to accidental illumination of the light responsive switch are completely avoided.

As will subsequently be described in detail, the timer of this invention automatically retimes itself within a reasonable period of time after a power failure. This automatic retiming is effected by the cooperation of the light responsive switch with the driven dial which makes one complete revolution in approximately 20 hours and then turns off the driving motor about four hours before the expected time of operation of the light responsive switch. If the power failure is of extensive duration, commences before dusk, and lasts throughout the hours of darkness, the photocell will not operate at all that day and the timer motor will remain off for an entire day. At dusk of the following day, normal operation of the timer is resumed when the light responsive switch turns the motor on, and the lights on. In the case where the power failure is of less than about 3%. hours duration the timer will automatically recycle itself in not more than one day. For example, suppose that the timer is set to turn the lights off hours after the light responsive switch turns the lights on, and that a power failure of 3 hours occurs one hour after the lights are turned on. The lights will not be turned off until 3 hours later than normal. However, the next day, the timer motor will run an extra 3 hours and thus will not turn off until one hour prior to the time of operation of the light responsive switch at dusk. Since the motor starts again when the light responsive switch operates the 3 hours are made up and the timer is retimed. Hence, even though the lights may be turned on late and/or turned otf late on the day of a short power failure, depending on the exact hour of the power failure, the proper cycle of operation will resume the following day.

Even in the worst conceivable situation, the cycle of the timer will be substantially inaccurate for two or three days at most, but will retime itself in not more than 4 days, and resume its proper cycle of operation, without any manual assistance. This is extremely important when it is realized that only several street lighting units are .normally controlled by a single timer because of current carrying limitations of the switches which control the lighting and hence, hundreds of timers may require resetting after a power failure in a larger city. Also, where an advertising company maintains several thousand billboards many of which are in remote locations the cost of retiming manually is indeed prohibitive.

In view of the foregoing an object of this invention is an electrically powered timer combined with a device responsive to a daily occurring natural condition to automatically retime the timer after a power failure;

Another object of this invention is an electrically powered automatically retiming timer combined with a light responsive switch to automatically operate a load ON at dusk and OFF several hours later.

Another object of this invention is an electrically driven timer which automatically turns itself off each day after a certain number of hours of operation and simultaneously conditions itself for operation by a light responsive switch, at dusl A further object is an automatically retiming timer combined with a light responsive switch, the timer being conditioned to operate a load at dusk in response to operation of the light responsive switch, prevent its operation by the light switch until again conditioned, and operate the load to another condition at a predetermined time after its initial operation by the light responsive switch.

A further object is a timer of unique construction especially adapted for use with a device responsive to a recurring natural condition to automatically retime the timer.

Another and further object is a unique timer including switches and circuitry especially adapted for use with a light responsive switch to control the operation of an electrical device and to automatically retime the timer to a proper operating cycle after a power failure.

A still further object is a timer having a unique switch actuator which is conditioned for operation by a driven dial, and is operated by a light responsive switch but only when conditioned.

Another and still further object is a timer in accordance with the above objects which is efiicient, reliable, economical to manufacture, and which is capable of switchin g very high current carrying loads.

The following specification, of which the accompanying drawings form a part, explains the manner in which the foregoing objects are attained in accordance with this invention. In the drawings:

FIG. 1 is a plan view of the timer of this invention;

FIG. 2 is a view in side elevation looking from right to left at the timer of FIG. 1;

FIG. 2A is a sectional view taken horizontally through the timer of FIG. 1 illustrating, in plan, switch operating slide bar members with latching and biasing means therefor and indicated by line 2A-2A of FIG. 4;

FIGS. 3-5 are each views in plan looking at the back of the timer of FIG. 1 and showing the positions of the various switches and operating elements for an operating cycle of the timer with:

FIG. 3 showing the timer with motor on and primary electrical load off;

FIG. 4 showing the timer with motor off and light sensitive device conditioned;

FIG. 5 showing the timer with motor on and primary electrical load on;

FIG. 6 is a fragmentary view of the front of the timer showing the switch operating assembly an instant before snap operation from olf to on, with the driven dial removed for clarity of illustration;

FIG. 7 is a fragmentary view of the back of the timer showing the switch operating assembly an instant before snap operation from of]? to on;

FIG. 8 is a view corresponding to FIG. 7 showing the switch operating assembly after snap operation to its on condition;

FIG. 9 is a view corresponding to FIG. 6 showing the switch operating assembly after snap operation to its on position;

FIG. 10 is a schematic diagram showing the electrical wiring of the timer, light sensitive switch, and electrical loads controlled by the timer; and

FIG. 11 is a graph showing a complete cycle of operationof the timer and light sensitive switch during a 24 hour period of time.

Referring now to the drawings in detail and particularly to FIGS. 1 and 2 there is shown a timer assembly 1 having a mounting panel in the form of a flat plate 2 and a flat terminal board 3 of insulating material generally coplanar with plate 2 and secured to and projecting below its bottom edge 4. Plate 2 and terminal board 3 are provided with suitable notches 5 to enable removably securing timer assembly 1 in a protective box type housing (not shown) when in use. A dial assembly 6 is mounted for rotation about an axis perpendicular to the plane of plate 2, this axis being offset toward the left side of the plate as seen in FIG. 1. Dial assembly 6 is driven by an electric motor 7 (FIG. 2) via suitable reduction gearing indicated generally at 8 to turn the dial one complete revolution in 20 hours.

Mounted on dial assembly 6 for rotation therewith is an on trip lever 9 having an on trip finger 9a and a lug 9b, and an off trip lever 10 having an ofi trip finger 10a, the off trip lever being spaced circumferentially from the on trip lever.

Pivotally mounted on plate 2 adjacent dial assembly 6 is a snap acting switch operator assembly 11 which is operated from the off position of FIG. 1 to the on position of FIG. 8 by on trip lever 9, and from the on position of FIG. 8 to the off position of FIG. 1 by oft trip lever 10, however, such operation can also be done manually.

At a location slightly above dial assembly 6 is a day omit mechanism indicated generally at 12, and mounted on plate 2. The purpose of day omit mechanism is to prevent a cycle of operation of the timer on any particular day or days of a week. This purpose is accomplished by day selector dial 13 and blocking lever 14 to prevent operation of switch operator assembly 11 from off to on during any preselected day or days of the week.

Fixed to terminal board 3 are a plurality of terminals 15-21 having terminal screws 15w-21a respectively to facilitate making electrical connections.

As shown in FIG. 3 terminals 15-21 project from the back face 22 of terminal board 3 and terminal screws 15a-21a extend through threaded portions of the respective terminals. A primary load switch 23 and an auxiliary load switch 24 are secured to the back of the terminal board. Primary load switch 23 includes a stationary contact 25 fixed to terminal 15, and a movable contact 26 aligned with contact 25, and fixed to a fiat leaf spring arm 27 of conducting material having an end secured to terminal 16 and which normally biases contact 26 to engage contact 25. Auxiliary load switch 24 is of similar construction having a stationary contact 28 fixed to terminal 18 and a movable contact 29 carried by a flat leaf spring arm 30 secured to terminal 17 and which normally biases contact 29 to engage contact 28. With switch operator assembly 11 in the off position as seen in FIG. 3, primary load switch 23 is open and auxiliary load switch 24 is closed. Terminals 19-21 at the left hand side of the terminal board (FIG. 3) are provided to facilitate making the necessary connections for the internal wiring (omitted in this View for purposes of clarity) for the timer.

Mounted on the 'back of terminal board 3 are a pair of switch actuators in the form of an inner slide bar 31 and an outer slide bar 32, the slide bars cooperating to operate the several switches of the timer in a manner which will subsequently be described in detail.

Each slide bar is generally rectangular, is formed from insulating material, and has a pair of aligned outwardly facing slots 33 and 34 at the ends thereof to mount the slide bars for sliding movement independently of each other on identical bushings 35 and 36 secured to opposite sides of the terminal board by screws 37. As best seen in FIG. 2 each bushing includes two reduced diameter portions 38, which receive the ends of slide bars 31, 32, and larger diameter bosses 38 on each side to mount the slide bars in spaced apart relation parallel to each other and parallel with the plane of terminal board 3. Such mounting of the slide bars permits them to slide in a direction generally parallel with edge 4 of plate 2.

Slide bars 31 and 32 are identical save that a V-shaped notch 39 in top edge 40' of outer slide bar 32 is offset slightly to the right of V-shaped notch 40 in the top edge 39' of slide 'bar 31. Mounted on plate 2 immediately above the slide bars and secured thereto with screws 4-2 is a single pole double throw microswitch 41 having an operating arm 43 with a V-shaped end 44 of suflicient width to extend across the top edges of both slide bars (FIG. 2A).

Arm 43 is spring biased to normally rest against top edges 39' or 40' of the slide bars, whereupon the switch is in a first position, and switches to its second position when notches 39 and 40 are aligned and end 44 drops into the notches, as shown in FIG. 4.

Secured to inner slide bar 31 is a rigid motion transmitting member 45 that has a leg 46 which projects upwardly beyond edge 39' of the slide bar and has a rectangular end which extends perpendicular to plate 2 and through an opening 48 in the plate. Secured to outer slide bar 32 is a similar member 49 having a leg 50 and an end 51 that extends perpendicularly through opening 52 of plate 2. Extending between members 45 and 49, as best seen in FIGS. 2A and 3, is a flat relatively thin stop plate 53 having outwardly opening slots 54 and 55 at opposite ends thereof. Stop plate 53 lies fiat on top edges 39 and 40 and is of sufiicient width to extend across both slide bars. The slots 54 and 55 are parallel with each other but are in spaced apart planes so that leg 46 extends into slot 54 and leg 50 extends into slot 55. The ends of a helically wound tension spring 56 are connected respectively to legs 46 and 50 by passing the ends of the spring through openings in the legs.

Mounted for pivotal movement about an axis perpendicular to plate 2 and spaced laterally of the slide bars is a latch arm 57 operated by a solenoid 58. One end of latch arm 57 has a bushing 59 secured thereto which is journalled on pin 60 fixed to plate 2 and extending perpendicularly therefrom. Latch arm 57 diverges in a direction away from pin 60 and has a fiat lower edge 61 with a latch finger 62 having an edge 62 that projects downwardly at a right angle from edge 61 and faces toward pin 60. Above latch finger 62 and spaced therefrom is a pin 63 which is disposed within a groove 64 of plunger 65 of solenoid 58. Within solenoid 58, immediately above plunger 65 is a compression spring (not shown) which urges the plunger downwardly when the coil of the solenoid is unenergized and correspondingly urges latch arm 57 downwardly against end 5-1 of member 42.

As best seen in FlGS. 3 and 4 slide bars 31 and 32 each have a pair of spaced apart downwardly facing openings 66 and 67 formed therein into which the ends of spring arms 27 and 30 extend. Opening 67 of outer slide bar 32 has a rounded switch operating projection 68 extending from its left hand edge. The left hand side of opening 67 of slide bar 31 has a flat face 68' in the plane of the left hand edge of the opening and is spaced from the end of contact arm 30 when slide bar 31 is in the position shown in FIG. 4. Hence, slide bar 31 does not operate switch 24. Opening 66 of both slide bars is identical and has at its right hand side a rounded switch operating projection 69 which functions to open switch 23 when the slide bars are in the FIG. 3 or FIG. 4 position. Opening 66 of both slide bars is of suflicient width that its flat left hand edge 69' does not engage contact arm 27.

As seen in FIGS. 3-5 slide bars 31 and 3-2 are operable equentially to three different positions. With switch operator assembly 11 in its olf position both slide bars are in the extreme left hand positions of FIG. 3. When so positioned the contacts of switch 24 are closed since switch operating projection 68 is spaced from contact arm 30, and the contacts of switch 23 are open due to the engagement of projection 69 with the end of movable contact arm 27. It is also to be noted that the side edge of end 51 of member 49 is spaced slightly from edge 62' of latch finger 62. When switch operator assembly 11 is operated to its on position member 45 is moved to the right with corresponding movement of slide bar 31, to the position of FIG. 4. Although inner slide bar 31 moves the same distance as member 45, outer slide bar 32 is moved by the action of tension spring 56, only far enough for end 51 to engage edge 62 of latch finger 62 and further movement of outer slide bar 32 in a direction to the right is prevented by the latch finger. With the slide bars in this position notches 39 and 40 are aligned and V-shaped end 44 of microswitch 41 is disposed in the notches and the microswitch is switched to its second position. Neither switch 23 nor 34 is operated by the movement of inner slide bar 32 when the switch operator assembly llis moved from its off position to its on position.

Operation of switches 23 and 24 occurs when the winding of solenoid 58 is energized. Solenoid 58 is energized in a manner that will subsequently be described in detail.

When the solenoid is energized plunger 65 is pulled upwardly and lifts pin 63 thereby pivoting latch arm 57 to release member 49 and permit outer slide bar 32 to slide to the right under the action of tension spring 56, the extent of movement of the slide bar to the right being limited by the engagement of leg 50 with the bottom edge of slot 55 of stop plate 53. Such movement of slide bar 32 to the position of FIG. moves operating projection 69 a sufficient distance away from contact arm 27 to permit the contacts of switch 23 to close and opens the contacts of switch 24 by the engagement of operating projection 68 with contact arm 30. Also, notch 39 is moved to the right which forces V-shaped end 44 of microswitch 41 upwardly onto edge 40" and thus returns the switch to its first position. When switch operating assembly 11 is again returned to its oil? position, either manually or under the action of off trip lever 10, the several elements of the timer are returned to the FIG. 3 positions. It is to be noted that during such movement of switch operating assembly 11 from on to off, inner slide bar 31 is moved to the left from the position of FIG. 5 by the action of switch operator assembly 11 on leg 47 of member 45. Leg 45 moves stop plate 53 which engages and moves leg 58 of member 49. Since member 49 is connected to outer slide bar 32, the outer slide bar is also moved to the left as switch operating assembly pivots from on to off, but such movement is via inner slide bar 31.

It is extremely important that movement of the slide bars occurs with a snap action to avoid arcing of the contacts of switches 23 and 24. As just described, movement of outer slide bar 32 to the right occurs with a snap action under the influence of tension spring 56 when slide bar 32 is released by operating the solenoid. Movement of both slide bars 31 and 32 to the left also occurs with a snap action under the influence of switch operator assembly 11 in a manner which will later be described in detail.

Referring now to FIG. 6, switch operator assembly 11 includes operating lever 70 mounted for pivotal movement on a pin 71 fixed to and projecting beyond both faces of plate 2. Operating lever 70 is formed from flat sheet metal and has a manual operating tab 72 (FIGS. 1, 2 and 2A) bent at an angle to the body of the operating lever to tacilitate operating the lever from one position to another manually. Mounted between operating lever 70 and plate 2 is a slider member 73 also formed from rigid sheet metal. The bottom end of slider member 73 has a tab 74 bent inwardly to extend through opening 75 in plate 2. Projecting from the top edge of opening 75 is a finger 76 with side edges 76' and 77 and tab 74 normally rests on one side or the other of finger 76.

Operating lever 70 has wing-like projections 77' and 7 8 extending from opposite sides thereof to provide edges 79 and 80 arranged to engage respectively tabs 81 and 82 which project from slider member 73 in a direction away from plate 2 to underlie edges 79 and 80. Slider member 73 has an elongated closed slot 83 with curved ends, and through which pin 71 extends. Spaced longitudinally from slot 83 is a slot 84 located between lug 74 and slot 83. Slot 84 receives rectangular end 47 of member 45 so that movement of slider member 73 from a position on one side of finger 76 to the other moves member 45 and correspondingly inner slide bar 31 which is secured thereto. It is to be noted that the sides of slot 84 are closely adjacent the side edges of end 47 and hence, slide member 73 determines the precise position of inner slide bar 31.

Switch operating assembly 11 also includes a mechanism mounted on the back of plate 2, as shown in FIG. 7. Mounted on the back of plate 2 for pivotal movement about pin 71 is a pivot plate 85 having a U-shaped cut out 86 at its lower end toprovide clearance for end 47 of member 45. Above pin 71 and adjacent an opening 58 of platae 2 pivot plate 85 is cut away to provide a generally arcuate slot '89 into which a rectangular tip 90 of operating lever 70 extends from the other side of plate 2 via opening 88. Formed from the material of pivot plate is a tab 91 located slightly radially inwardly of tip 90, relative to pin 71, tab 91 being bent to project in a direction away from plate 2.

Mounted for pivotal movement on a bushing 92 concentric with pin 71 and on which pivot plate 85 also pivots, are a pair of offset lever arms 93 and 94 each formed of flat sheet metal and superposed one on the other. Lever arm 93 includes a leg 95 projecting upwardly from bushing 92 and a parallel offset leg 96 projecting downwardly and terminating at an outwardly curved end 97 having a notch 98 at its outer edge. Lever arm 94 is identical to lever arm 93 inverted relative to the plane of plate 2 so that leg 99 projects upwardly, and a leg 1% projects downwardly and terminates in an outwardly curved end 101 with not-ch 102 in its outer edge. A helically wound tension spring 103 has its ends retained in notches 91% and 102 to normally maintain the inner side edges of legs 95 and 99 respectively in engagement with the side edges of tip 95 and tab 91. A pin 103 is secured to plate 36 at a location slightly above cut out 89, the pin extending through an opening 1M; of plate 2 and projecting beyond its front face. A torsion spring 105 (FIG. 6), mounted on pin 71 has ends 1% and W7 that engage beneath tabs 81 and 82 to normally bias slider member 73 upwardly so that lug 74 is urged against the upper edge of opening 75 on one side or the other of finger 76.

Operation of the switch operator assembly will now be described in detail. Operation of switch operator assembly 11 from one position to the other is accomplished by moving operating lever 70 in the appropriate direction either manually or by the action of on trip finger 9a or off trip finger 16a. As shown in FIG. 6 operating lever 70 has already been pivoted somewhat in a clockwise direction by the operation of on trip finger 9a which projects from on trip lever 9 and engages a curved on operating lug 108 formed from the material of operating lever 70 and which is disposed in the path of travel of on trip finger 9a whenever switch operator assembly 11 is in its off position. With operating lever 70 initially pivoted by on trip lever 9, tip of the operating lever engages the inner edge of leg to pivot lever arm 93 in a counterclockwise direction as seen in FIG. 7 from the back of the timer. Such pivotal motion tensions spring 103 since lever arm 94 is restrained from movement in a counterclockwise direction by the engagement of leg 99 with tab 91 of pivot plate 55. (Pivot plate 85 is rest-rained fro-m movement by the engagement of U-shaped opening 87 with a side edge of end 47 of member 45.) As viewed from the front of the timer in FIG. 6, engagement of end 47 with the side edges of slot 84. restrains ends 47 against movement. The slider member 73 is prevented from pivotal movement at this time by the engagement of lug 74 with the side edge 77 of finger 76. As operating lever 70 is further pivoted in a clockwise direction (FIG. 6) edge 79 engages tab '82 of slider member 73 and pushes the slider member downwardly as operating arm 70 pivots. During such movement the slider member is guided by slot 83 which encircles pin 71 and slot 84 which encircles end 47. When operating lever 70 is pivoted enough to move slider member 73 a sufficient distance downwardly so that lug 74 clears finger 76, switch operator assembly 11 snaps over to its on position as shown in FIG. 8. The snap action occurs as the results of the rapid release of energy stored in tension spring 103 during the pivotal movement of operating lever 79 toward the snap over position. As slider member 73 pivots from its off position to its on position tab 82 likewise pivots away from edge 79 and hence, when slider member 73 reaches the on position of FIG. 8 ends 1% and 107 of torsion spring bias the slider member upwardly so that lug 74 engages in the notch adjacent side edge 76 of finger 76.

The operation from on to off of switch operating assembly 11 takes place in an identical manner as oif to on save that the snap operation is in the opposite direction. Operation from on to off can be accomplished either manually or by the action of off trip pin a, of off trip lever 10, against 011 operating lug 109 integral with an arm 110 and extending from the side of operating lever 70. When operating lever 70 is pivoted in a counterclockwise direction from the position of FIG. 8 edge 80 engages tab 81 to push slider member 73 downwardly against the action of torsion spring 105 until lug 74 clears side edge 76' of finger 76, whereupon the entire switch operator assembly snaps over to the off position, the snap action again being the result of the sudden release of the energy stored in spring 103 when tensioned by the initial movement of operating lever 70.

Day omit mechanism 12 prevents operation of switch operator assembly 11 from its off position to its on position, during any selected day of a week. This result is efiected by the cooperation of blocking lever 14 with day selector dial 13.

Referring now to FIGS. 1, 2 and 6, day selector dial 13 includes an indicator wheel 111 fixed to one end of a b ushing 111', and an index wheel 112 fixed to the other end of bushing 111'. Bushing 111' is mounted for rotation on shaft 112 projecting perpendicularly from plate 2. Index wheel 112 is flat and has seven equally spaced projecting arms 113. Indicator wheel 111 has seven equally spaced rounded bottom recesses 114 formed at the periphery of the wheel. Between each pair of adjacent recesses 114 is a threaded opening 114 adapted to receive a selector pin 115 which is similarly threaded to project beneath wheel 111 when in position, as shown in FIG. 2.

Blocking lever 14 is mounted for pivotal movement about a pin 115' projecting perpendicularly from plate 2 (FIG. 6). Main body 116 of blocking lever 14 is formed of flat sheet metal and is located in a plane below indicator wheel 111 so that a torsion spring 117 normally biases main body 116 partially beneath indicator wheel 111. Projecting from main body 116 in a direction away from plate 2 is a stop pin 118 which normally engages one of recesses 114 due to the bias of spring 117, and prevents free rotation of day selector dial 13. As best seen in FIG. 6, the upper edge of body 116 is provided with a shallow U-shaped recess 119 which faces toward the axis about which day selector dial 13 rotates. Adjacent recess 119 is an edge 119' disposed in the path of travel of a pin 115 when the pin is inserted in one of the threaded openings 114' of indicator wheel 111. Projecting laterally from the side of main body 116 opposite the side where body 115 is pivoted is an end lever 120 having an upwardly extending end which presents a flat blocking face 120'. As best seen in FIG. 1, one of arms 113 of day selector dial 13 is disposed in the path of travel of lug 9b of on trip lever 9. During each revolution of dial assembly 6 lug 9b engages a side edge of one of arms 113 to index day selector dial 13 one-seventh of a revolution. Since dial assembly 6 makes only one revolution each day, day selector dial 13 is correspondingly indexed only of a revolution each day. Lug 9b operates to rotate day selector dial 13 in a counterclockwise direction. Rotation of the day selector dial pivots blocking lever 14 in a direction away from indicator wheel 111 by virtue of the engagement of the periphery of the indicator wheel with pin stop 118. Continued movement of day selector dial 13 under the action of lug 9b permits pin 118 to enter the next adjacent recess 114 of the indicator wheel, simultaneously with movement of arm 113 beyond the path of travel of lug 9b. The cooperation of pin 118 with one of recesses 114 maintains day selector dial 13 in the proper position to be indexed by lug 9b the next time the lug passes the day selector dial. If it is desired to omit a cycle of operation of the .timer on any particular day of the week a selector pin 115 is threaded into an opening 114' corresponding to the day of the week when operation is to be omitted. With a selector pin 115 so mounted edge 119' of blocking lever 14 extends into the path of travel of the selector pin. Referring now to FIG. 6, as indicator wheel 111 is indexed on the preselected day the selector pin will engage edge 119 thus pivoting blocking lever 14 to the dotted line position, whereupon selector pin 115 enters recess 119 at the edge of body 116 just as the arm 113 engaged by lug 96 moves out of the path of travel of the lug. Blocking face 120' is then disposed in the path of travel of pin 103 fixed to pivot plate 85. In this position the blocking lever prevents pivot plate 85 from moving from its FIG. 7 position to its FIG. 9 position. Hence, pivotal movement of operating lever 70 in a counterclockwise direction under the action of on trip pin 9a is effective to merely pivot the operating lever and the remainder of switch operating assembly 11 is held in its off position because pivot plate 85 i blocked against movement. When operating lever 70 is released by on trip pin 9a the lever merely snaps back to its original off position under the action of tension spring 103. When day selector dial is again indexed the following day, selector pin 115 moves out of reces 119 to a new position to release blocking lever 14 whereupon the timer resumes its normal cycle of operation. As previously stated dial assembly 6 is driven one revolution in 20 hours by motor 7 via reduction gearing 8. Motor 7 is a standard synchronous type timer motor with self-contained gearing within housing 121 to rotate motor pinion 122 at the rate of revolution per minute. With motor 7 mounted on the back of plate 2 as shown in FIG. 2 pinion 122 extends through an opening in the plate to mesh with and drive spur gear 123. Gear 123 is fixed to and thus drives a smaller diameter gear 124, both gears being mounted for rotation on a shaft 125 fixed to plate 2. Gear 124 drives a larger diameter gear 126 fixed to a bushing 127 mounted for rotation on a shaft 128 fixed to plate 2. Fixed to dial assembly 6 is a bushing having a sleeve 129 of similar outside diam eter to a sleeve 13!) of bushing 127. The sleeves 129 and 130 are each mounted for rotation on shaft 128 with their end faces in abutting relation. Encircling sleeves 129 and 130 is a helically wound torsion spring 131 which cooperates with the sleeves to provide a conventional one way clutch which permits manually rotating dial assembly 6 and sleeve 129 in a clockwise direction only, relative to bushing 127.

Since dial assembly 6 is to rotate only once in the 20 hours and since pinion 122 makes revolution per minute the gear train comprised of gears 123, 124 and 1'26 are appropriately selected to provide a reduction ratio of 24:1. Shaft 128 extends completely through dial assembly 6 and terminates at an end which is internally threaded to receive a screw 132 which secures setting pointer 133 in a fixed position. In practice setting pointer 133 is pre-set to the proper circumferential position at which the on and off trip levers operate the switch operator assembly 11.

Also mounted on plate 2 adjacent the upper edge thereof is an indicator light 134 and a momentary contact push button switch 135, the purposes of which will subsequently be described in detail.

For purposes of clarity of illustration the internal wiring of the timer is not shown in detail in FIGS. 1-5. FIG. 10 shows the wiring for the timer in schematic, as well as the wiring of a light response switch 136, and external wiring 137 for a primary load 133, in the form of a bank of electric light bulbs, and an auxiliary load 1.39. Terminal board 3 is shown in dotted lines 139' and terminals 1521 are shown in their appropriate positions as viewed from the front of the timer to facilitate explanation.

The internal wiring is as follows. Movable contact arm 1 40 of single pole double throw switch 41 is connected to terminal 20 by line 141. Motor 7 is connected between terminal 21 and stationary contact 142 of switch 41 by lines 143 and 144. The winding of solenoid 53 is connected between terminal 19 and the other stationary contact 145 of switch 41 by lines 146 and 147 respectively. As previously described, movable contact 26 of switch 23 has its spring arm 27 fixed to terminal 15 and stationary contact 25 of switch 23 is fixed to terminal 16. Similarly, movable contact 29 of switch 24 has its spring arm 30 fixed to terminal 18 and stationary contact 28 of switch 24 is fixed to terminal 17. Indicator light 134 is connected between terminals 19 and 20 via lines 146 and 141. Push button switch 135 is connected between terminals 19 and 21 via line 147 and line 148.

Light responsive switch 136 is external to the timer and includes a cadmium sulphide photoconductor 149 connected in series with a winding 150 of a relay 151. Relay 151 has a movable contact 152 which is spring biased to engage its stationary contact 153 when winding 150 is unenergized. In the position shown in FIG. 10 winding 150 is energized and hence, the contacts of relay 151 are open. Stationary contact 153 is connected to terminal 19 by line 154. Movable contact 152 and one side of winding 150 are connected to terminal 21 via line 155, and line 156 completes the series connection of photocell and relay between terminals 20 and 21.

The several electrical components of timer assembly 1, light responsive switch 136, and external wiring 137 are powered by standard 120 volt 6 cycle current from leads 15 7 and 158 of a power line. Electricity to operate both the timer and light sensitive switch 136 is supplied by power leads 157 and 1 58 connected to terminals 21 and 20 respectively. Lamps 138 controlled by the timer, are connected between power lead 158 and terminal 15 and lamps 138 light when switch 23 is closed. Auxiliary load 1 39 is connected between power lead 158 and terminal 18. Power lead 157 is also connected to both terminals 16 and 17 via lines 159 and 160.

Power for photocell 149 and relay 151 is thus supplied from power leads 1'57 and 158 via terminals 21 and 20 and lines 156 and 1 55. Photoconcluctor 149 is of the cadmium sulphide type that has a low resistance when exposed to light and a very high resistance when dark. Relay 15 1 is selected to pull in and maintain contacts 152 and 153 open when photoconductor 149 is exposed to a daylight value of natural light. When the light to which photoconductor 149 is exposed diminishes to a predetermined value the resistance of the photoconductor increases and the voltage at winding 150 decreases to below the drop out voltage of the relay, whereupon the armature of the relay drops out and contacts 152 and 153 close. When contacts 152 and 153 are closed terminal 19 is connected to terminal 21 and indicator lamp 134 lights. However, solenoid 58 is operated only when contact arm 140 is switched to its second position to engage fixed contact 145. It is to be noted that push-button switch 135 is connected in parallel with light responsive switch 136 so that closing switch 135 has the same effect as closing contacts 152, .153 by the ope-ration of photoconductor 149.

Motor 7 is energized only when microswitch 41 is in its first position with contact arm 140 engaging contact 142, and the motor stops whenever switch 41 is in its second position in which solenoid 53 can be energized. it is thus apparent that the circuit indicated generally at 161, including motor 7, contacts 140 and 142 of switch 41, and line 141 may aptly be termed a motor control circuit. Also, line 141, contacts 141} and 145 of switch 41, line 146, and light responsive switch 136 form a load switch control circuit indicated generally at 162, since energization of solenoid 58 can operate load switches 23 and 24 from one condition to another. 7

It is to be noted that solenoid 58 when operated has no effect on the condition of switches 23 and 24 unless outer slide bar 32 is biased toward the right under the action of spring 56 as shown in FIG. 4. With the outer slide bar in this position the timer is termed conditioned since operation of solenoid 58 is then effective to lift latch finger 62 to release slide bar 32 and operate the several switches of the timer. When outer slide bar 32 is not biased by spring 56, as is the case when the slide bar occupies the positions of either F168. 3 or 5, operation of the solenoid merely functions to lift latch finger 62, but the position of outer slide bar 32 remains unchanged since there is no force acting to move the slide bar.

Referring now to FIG. 10, it seems apparent that switch 41 could be a single throw switch and that contact 145 of control circuit 162 could be eliminated merely by connecting a lead 163 (shown in dotted line in FIG. 10) between line 141 and line 147, without affecting the basic operation of the timer. With lead 163 so connected control circuit 142 operates solenoid 58 whenever light sensitive switch operates to close contacts 152 and 153. However, such operation has no effect on the timer unless slide bar 32 is in its FIG. 4 position and biased to the right under the action of tension spring 56, this conditioned position occurring by the action of on trip lever 9, or alternatively by manual movement of switch operator assembly 11 from its off position to its on position.

Movable contact 141] and fixed contact 145 of switch 41 do however, accomplish an important function. Considering FIG. 10 with lead 163 is eliminated, solenoid 58 can be energized only when switch 41 is in its second position in which contact engages contact 145. With switch 41 in the FIG. 10 position and lead 163 eliminated contacts 152 and 153 may open and close several times each day due to clouds in the day time or lightening at night time, for example, without any danger of arcing or pitting at the contacts since no current is carried by circuit 162 because contacts 140 and are open. Hence, switch 41 is provided in the form of a double throw switch to prevent damage to contacts 152 and 153 because of unwanted operation of light sensitive switch 136. It is to be understood however, that contact 145 is not absolutely necessary and could be eliminated by the use of lead 163. However, it a different operator is substituted for outer slide bar 32 to operate switches 23 and 24, and is so arranged that the switches are operated each time solenoid 58 is energized the same end result of conditioning the timer for operation would be provided by contacts 140 and 145. Hence, where the load to be controlled requires only several amperes of current, high current carrying switches such as 23 and 24 need not be used and a relay with appropriately connected contacts could be substituted for solenoid 58.

The operation of the timer can be best visualized by reference to FIG. 11 which shows a complete cycle of operation of the timer for any particular day. For purposes of explanation it is assumed that the time of year is such that the light sensitive switch operates at approximately 7 pm, the controlled load is a. lighting circuit, the lights are to be turned off at 11 pm, four hours after they are turned on, and the timer motor is on only 2 0 hours a day. During the hours between 11 pm. and 3 pm, the several elements of the timer are in their FIG. 3 position in which the motor is on to drive dial assembly 6, the lights are off, and the switch control operator (slide bar 32) is not conditioned. At approximately 3 pm, on trip finger 9a of the dial assembly operates switch operator assembly 11 from its 011 position to its on position, with corresponding operation of slide bars 31 and 32 to the FIG. 4 position. As shown in FIG. 4 slide bar 32 is biased to the right by the action of tension spring 56, but the slide bar is held against movement by latch arm 57 which engages end 51 of member 49. Primary load switch 2 3 is open, auxiliary load switch 24 is closed, and double throw switch 41 is in its second position, since notches 3 9 and 40 of the slide bars are aligned to permit end 44 to pivot counterclockwise into the notches. With switch 41 in this position movable contact 140 engages fixed contact 145 and circuit 162 will be energized when contacts 152 and 153 of light responsive switch close. Since contacts 140 and 142 are now open motor 7 is off and dial assembly 6 is thus stopped. At dusk (which it is assumed occurs at 7 p.111.) the intensity of light received by photocondu'ctor 14-9'has reduced to a value to cause relay 1-51 to drop out thereby closing contacts 152 and 153. Solenoid 58 is then energized and pivots latch arm 57 counterclockwise to release outer slide bar 32 whereupon the slide bar is snapped to the position of FIG. 5 under the action of tension spring 56. Such operation of the slide bar closes the contacts of primary load switch 23, opens the contacts of auxiliary load switch 24, and switches switch 41 back to its first position by moving operating arm 43 counterclockwise out of notch 39 so that the arm rests on edge 40 of slide bar 32. Operation of the primary load switch 23 turns the lights on and turns the motor on. At the same time control circuit 162 is disconnected from the power supply at terminal 20 and outer slide bar 32 is in an unconditioned state. Obviously any extraneous light reaching the photoconductor, due to accidental illumination by lightening or automobile headlights, has no effect on the timer since the timer is not conditioned for operation.

Four hours after the lights are turned on, off trip lever of the dial assembly reaches off operating lug 109 of operating lever 70 and pivots switch operator assembly 11 back to its off position. As previously explained movement of switch operator assembly 11 from on to off returns slide bars 31 and 32 to the FIG. 3 position wherein primary load switch 23 is open and auxiliary load switch 24 is closed. End 44 of operating arm 43 of switch 41 rests on edge 39' of slide bars 31 and hence, circuit 162 cannot be energized by light responsive switch 136. Since motor 7 is off from 3 pm. to 7 pm. it is apparent that dial assembly 6 is driven by the motor to make a complete cycle of operation between the hours of 7 p.m. of one day and 3 p.m., of the following day, a period of 20 hours.

Automatic retiming takes place in the following man her. The time interval of four hours during which the motor is off is termed a pause period, for convenience. During this pause period motor 7 is off and the dial assembly 6 is stopped. In the event of power failure the timer can gain as much as four hours each day i.e. the duration of the pause period until a proper cycle of operation is resumed. Assume for example that a power failure occurs and that the power is off for three hours. Also .asume that the power failure occurs at about 8 p.rn. Since the motor is normally on between the hours of 7 pm. of one day and 3 p.m. of the following day the effect of the power failure is to shut the motor off for a period of 3 hours, and the lights also go off. When power is resumed the motor starts again and the lights go on. The lights remain on for an extra 3 hours and are thus not turned off until 2 a.m. by the operation of off trip lever 10. On the following day on trip lever 9 turns the motor off and conditions the switch control for operation but not until 6- pm. because the driven dial has been retarded 3 hours by the failure of power on the preceding day. At 7 pm, however, light responsive switch operates in the normal manner and the lights are turned on and the motor is turned on. Hence, the light responsive switch has operated to decrease the duration of the pause period when-the motor is off and the dial assembly has thus regained the three hours lost during the power failure on the previous day. Had the three hour power failure occurred during the pause period the lights may have been turned on later and turned off later depending on the exact time of the power failure. However, the time lost if any, during the power failure would have been regained on the following day.

Now consider the automatic retiming of the timer, set to turn lights off at 11 p.m., as before, when a power failure of extensive duration occurs. Assume that the power failure again occurs at 8 pm. but that power is off for 12 hours. Because of the operation of the timer at 8 p.m. the parts of the timer are in the FIG. 5 position, with primary load switch 23 closed. When power is resumed at 8 a.m. the following day the lights go on since switch 23 is still closed. Three hours later the motor has driven the dial assembly to a position to operate primary load switch 23 and turn the lights off. Since the power failure was of 12 hours duration the timer motor is not turned off again until 3 a.m. and the switch control is simultaneously conditioned for operation. Since it is dark at 3 a.m. light responsive switch immediately operates to turn the lights on and turn the motor on. Hence, four hours of the 12 hours lost during the power failure has been regained. The lights remain on for four hours and are turned off at 7 a.m. by operation of the off trip lever. The following day the motor is turned off and the switch control conditioned for operation at 11 pm. and the light responsive switch immediately operates to turn the lights on and turn the motor back on. Hence, another four hours is gained. The lights are then on from 11 pm. until 3 a.m. On the next day the on trip lever turns the motor off and conditions the switch control at 7 pm, and the light sensitive switch immediately operates to turn the lights on and turn the motor back on. Thus, another four hours is gained and since the light sensitive switch was originally set to turn the lights on at 7 pm. the proper cycle of operation of the timer is resumed. Even in the worst possible situation a proper cycle of operation will be resumed within 3 or at most 4 days after the power failure.

With reference to FIG. 1 it is seen that dial assembly 6 includes a circular dial 164 having a flat face 165, the dial being formed of substantially flat sheet material. The dial carries indicia with numerals 0-10 identified as hours of light on. Since the dial rotates only once in 20 hours the numerals 0-10 occupy exactly one half of the dial face. The other half of the dial face is identified as daylight hours since that portion of the dial is normally adjacent setting pointer 133 during the daylight hours.

On trip lever 9 is fixed to the dial at the numeral 0 position. Ofi trip lever 10 is r-emovably secured to the dial by set screw 166. The off trip lever may thus be adjusted manually to any position circumferentially of on trip lever 9 to adjust the length of time that load switch 23 remains closed and the lights controlled by the timer are on. As shown in FIG. 1, the off trip lever is set at numeral 4 whereupon the lights remain on for 4 hours.

In View of the foregoing description it is apparent that load switch 23 is operated on by slide bar switch operator 32 when the operator is conditioned and solenoid 58 is energized by operation of the light sensitive switch 136. Slide bar 32 is conditioned by operation of the dial assembly which also conditions control circuit 162 by operating switch 41. Since switch 41 is operated, motor 7 is off and the dial is stopped. After load switch 23 is operated on in response to operation of the light sensitive switch the load switch is opened by the action of off trip lever 10 which operates the slide bars and the switch operating assembly to the off position.

It is to be appreciated that although the timer of this invention has been described primarily as a control device for an electric lighting circuit, the timer could be used to control any electrical device or appliance which it is de=ired to automatically turn on at dusk and turn off a certain number of hours thereafter. As explained in detail the timer will also automatically retime itself to a proper preset cycle of operation Within several days after a power failure.

Although a preferred embodiment of the timer is shown and described it is to be understood that numerous changes can be made without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

1. In an automatically retiming timer, the combination comprising terminal means adapted to be connected to a power supply line; a motor; a driven device driven by said motor to make a complete cycle of operation in less than twenty-four hours and only when said motor is connected to said terminal means; a load switch having a first state and a second state; a light sensitive device operable in response to a predetermined value of natural light to connect said motor to said terminal means and to place said load switch in the first state only when said timer is conditioned for operation thereby starting the cycle of operation of said driven device; said driven device having control means to condition said timer for operation and to disconnect said motor from said terminal means at a predetermined time before the expected time of operation of said light sensitive device to terminate the cycle of operation of said driven device and provide a pause period during which said motor and driven device are inactive, and to place said load switch in the second state at a time after its placement in said first state whereby a load controlled by said load switch is placed in a first state at the time of occurrence of said predetermined value of natural light and in a second state at a time thereafter; and said driven member is automatically retimed for a proper cycle of operation after a power failure by eliminating said pause period to gain time equal to the duration of said pause period, until the time lost during the power failure is approximately regained.

2. A timer in accordance with claim 1 in which said driven device includes a dial, and a cycle of operation is completed during one complete revolution of the dial.

3. A timer in accordance with claim 1 in which said light sensitive device includes a photoconductor of the cadmium sulphide type and a switch so arranged that exposure of the photoconductor to a predetermined diminishing value of natural light turns said switch On.

4. A timer in accordance with claim 1 in which said load switch is On on its first state, and Off in its second state.

5. In an automatically retiming timer, the combination comprising terminal means adapted to be connected to a power supply line; first circuit means connected to said terminal means and including an electric motor and a motor switch means to turn said motor Off and On; a dial connected to and driven by said motor only when said motor is On and to complete a cycle of operation in less than 24 hours; second circuit means including a light sensitive device and an actuator which operates in response to operation of said light sensitive device only when said timer is conditioned for operation; a load switch having a first state and a second state; a switch operator responsive to operation of said actuator to operate said motor switch means to turn said motor On and to place said'load switch in the first state thereby starting the cycle of operation of said dial; first means carried by said dial and operate said switch operator to place said load switch in the second state at a selected time after its operation to said first state; and second means carried by said dial to operate said switch actuator during a predetermined time period before the expected operation of said light sensitive device, and cause said motor switch means to turn said motor Off and condition said timer for operation thereby terminating the cycle of operation of said dial.

6. A timer in accordance with claim 5 in which said switch operator includes a spring to bias said operator from one position to another, and said operator is retained in said one position by said actuator whenever said timer is conditioned for operation.

7. A timer in accordance with claim 5 in which; said second circuit means further includes a manually operable switch in parallel with said light sensitive device to operate said actuator manually whenever said timer is conditioned for operation.

8. A timer in accordance with claim 5 in which said cycle of operation is completed during one complete revolution of said dial.

9. A timer in accordance with claim 5 in which said i8 first means carried by said driven dial is an Off trip lever, and said second means carried by said driven dial is an On trip lever.

10. A timer in accordance with claim 5 in which said load switch is On in said first state and is Off in said second state, and said load switch is operated Off at a certain preselected period of time after it is operated On.

11. A timer in accordance with claim 5 in which said second means carried by said driven dial is an On trip lever, and operation of said switch operator by said On trip lever occurs approximately twenty hours after said motor is turned On.

12. A timer in accordance with claim 5 in which said switch operator is comprised of a first member and a second member each slidable along parallel spaced apart paths, said members being moved conjointly in response to said second means carried by said dial, and independently of each other, in response to said first means carried by said dial and in response to operation of said light sensitive device.

13. A timer in accordance with claim 5 in which said switch actuator is a solenoid operated latching device operable to release said switch operator when said solenoid is energized.

14. In an automatically retiming timer, the combination comprising terminal means adapted to be connected to a power supply line; first circuit means connected to said terminal means and including an electric motor and first switch means to turn said motor Off and On; a dial connected to and driven by said motor only when said motor is On and to complete a cycle of operation in less than twenty-four hours; second circuit means including second switch means which when turned On conditions said second circuit for operation, a light sensitive device, and an actuator operable in response to operation of said light sensitive device but only when said second circuit means is conditioned for operation when said second switch means is turned On; a load switch having a first state and a second state; a switch operator responsive to operation of said actuator to operate said first switch means and turn said motor On, and to place said load switch in the first state thereby starting the cycle of operation of said dial; first means carried by said dial to operate said switch operator and place said load switch in the second state at a time after its placement in said first state; and second means carried by said dial to operate said switch operator several hours before the expected time of dusk and operate said first and second switch means to turn said motor Off and condition said second circuit means for operation by said light sensitive device thereby terminating the cycle of operation of said dial.

15. A timer in accordance with claim 14 in which said second switch means is turned Off simultaneous with operation of said load switch to saidfirst state, to deactivate said second circuit means,

16. A timer in accordance with claim 14 in which said first and second switch means are comprised of the same two position switch.

17. In an automatically retiming timer the combination comprising: an electric motor; terminal means connectable to a source of electric power; a dial driven by said motor only when said motor is connected to said terminal means to complete a cycle of operation in less than 24 hours; a motor switch connected between said motor and said terminal means and operable to turn said motor On and Off; a load switch operable On and Off to control a load circuit; a switch operator operable to a first position; a second position, and a third position; said operator being effective; in said first position to maintain said motor switch On and said load switch Off, in said second position to maintain said motor Off and said load switch Off, and in said third position to maintain said motor switch On and said load switch On; first means carried by said driven dial to operate said operator from its first position to its second position once each day;

1 7 second means carried by said dial to operate said operator from its third position to its first position once each day; and an actuator operated by a light sensitive device at dusk and efiective to operate said operator only from its second position to its third position in response to operation of said light sensitive device.

18. A timer in accordance with claim 17 which further includes means operated 'by said dial to prevent a cycle of operation on any preselected day of a predetermined period of time.

18 References Cited UNITED STATES PATENTS ORIS L. RADER, Primary Examiner.

T. B. J OIKE, Assistant Examiner. 

